I was 24 before I got interested, though looking back, I can see some hints of interest before. I can totally see how someone could be older before they would get into the lifestyle, mainly because of the social stigma. With a lot of people, it was something they'd just never been exposed to, so it never crossed their minds that they might like it. Then when they are exposed to it, they like it and things get moving.

I definitely think younger people are starting to get into it more, since the info is more out there and kink is more accepted.